In the manufacture of polyene antibiotics, such as amphotercin B and nystatin, broth containing the antibiotic is filtered to remove the antibiotic solids, the solids are extracted with acidified methanol, the pH of the antibiotic rich methanol is raised to a convenient level, and the antibiotic is crystallized from the methanol. The crystals may then be formulated to produce topical creams and ointments.